Wayne Whitney wrote:
On 2008-04-09, dpb wrote:

Just plumbers' tape (the perforated metal strapping) would work fine
as long as use adequate fasteners.

Yeah, I thought of plumber's tape, but I was looking for something
more rigid. An expandable bar would work great.

Well you could either rig up something or use the expanding light mounts
or similar and I suspect (although I've not searched extensively)
there's something very similar for plumbing supports as well available.

But, the plumbers tape will probably just as simple and since it is
flexible will undoubtedly be be more quiet. Rigid w/o a a cushion
somewhere -- vibration/noise.

But, one has to ask why, in this day and age one would use cast
iron?

Cast iron is quieter and I may wish to finish my basement.

I'd go for the PVC for DWV and insulate around it w/ solid foam or
similar for the sound retardation, meself...

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